Links Between Epilepsy and Cancer?

Epileptics have higher risks of some types of cancer

(RxWiki News) Here’s an interesting fact. Epilepsy is fairly common in Denmark. About 1.5 percent of the Danish population has this brain disorder that causes seizures. A recent study looked at cancer risks associated with the disease and its treatment.

Scientists have been debating for decades about whether or not the powerful medicines used to treat epilepsy increase an individual’s cancer risks.

After studying the entire Danish population, a new study found little or no association between epilepsy medications and increased cancer risks.

However, researchers did discover that the disease itself may increase the risk for certain cancers.

"Work with your doctor to find the right dose of all medications you take."

Jeanette Kaae and colleagues from the Department of Epidemiology Research at the Statens Serum Institut in Copenhagen, Denmark, gathered information on 4,803,613 Danish residents over the age of 16, of whom 97,318 had a known epilepsy diagnosis.

The aim of this study was to establish whether medications used to treat epilepsy increase the risk for cancer.

The researchers looked at the wide range of medications used to treat the convulsive disease. A total of 22 medications were part of this analysis, some of which are used to treat conditions other than epilepsy.

Some of the medications included Lamictal (lamotrigine), Keppra (levetiracetam), Lyrica (pregabalin) and Zonegran (zonisamide).

The researchers found small increased risks (4-11 percent) of esophageal, stomach, intestine, lymph system, male genital tract, skin and urinary tract cancers among non-epileptics taking anti-epileptic medications (any medication) compared to non-users of these medications.

Non-epileptics taking these anti-epileptic medications also had 23 to 59 percent greater risks of liver, mouth and throat and respiratory tract cancers than did people without epilepsy who didn’t take these medicines.

People with epilepsy who were not taking any medications for the condition had small to moderate increased risks (17-35 percent) of cancer of the digestive and respiratory organs, compared to people without the disease.

Epileptics not taking any medicines, however, had a two-fold risk of central nervous system cancers and a three-fold greater risk of cancers of the mouth and throat compared to non-epileptics.

Adding medications did not further increase the risks of oral, digestive or respiratory cancers. 

Epileptics taking medications did have a nearly four-fold increased risk of central nervous system cancers and a 41 percent increased risk of liver cancer.

“For epileptics both with and without a record of anti-epileptic medication use, we observed strong associations between having epilepsy and the risks of central nervous system (200-400 percent increased risk) and mouth and throat (200-300 percent increased risk) cancers, as well as a modest association (30-35 percent increased risk) between epilepsy and the risk of respiratory tract cancers,” the authors wrote.

“The fact that there were generally no differences in cancer risk for epileptics who were taking medication for their condition and those who were not suggests that it is not primarily anti-epileptic medications that are responsible for the increased cancer risk among epileptics but epilepsy itself or another aspect of epilepsy diagnosis or treatment,” the authors concluded.

This study was published in the July issue of the International Journal of Cancer.

The research was supported by the Danish Medical Research Council. No conflicts of interest were disclosed.

Review Date: 
August 2, 2013